A physical assault carries a high chance of being noticed, and unless carried out by law enforcement, a significant chance of being punished with jail time. So it's not something that has a high chance of happening. Additionally, it's hard to defend against, and you definitely don't want to defend against a SWAT team.
Whereas a bored teenage neighbor could attack your wireless network with a very small chance of being detected. Or with a sensitive directional antenna it doesn't even have to be your neighbor if the goal is just to sniff traffic. Plus, the only cost to you in defending against this attack is entering a more complex password on new devices. Stick a note on the fridge or choose a phrase.
Whereas a bored teenage neighbor could attack your wireless network with a very small chance of being detected. Or with a sensitive directional antenna it doesn't even have to be your neighbor if the goal is just to sniff traffic. Plus, the only cost to you in defending against this attack is entering a more complex password on new devices. Stick a note on the fridge or choose a phrase.